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\newtheorem{notation}[theorem]{Notation}
\newtheorem{problem}[theorem]{Problem}
\newtheorem{proposition}[theorem]{Proposition}
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\begin{document}
La soluci\'{o}n de la ecuaci\'{o}n $3^{2x}=\dfrac{1}{4}$ es:\mathstrut
\newline\qquad a) $x=-\dfrac{1}{2}\dfrac{\ln4}{\ln3}\qquad\qquad$b)
$x=-\dfrac{1}{2}\dfrac{\ln3}{\ln4}\qquad\qquad$c) $x=-\dfrac{1}{4}\dfrac{\ln
2}{\ln3}\qquad\qquad$d) $x=\dfrac{\ln4}{\ln3}$

La soluci\'{o}n de la ecuaci\'{o}n $7^{3x}=\dfrac{1}{2}$ es:\medskip
\newline\qquad a) $x=-\dfrac{1}{3}\dfrac{\ln2}{\ln7}\qquad\qquad$b)
$x=\dfrac{1}{3}\dfrac{\ln2}{\ln7}\qquad\qquad$c) $x=-\dfrac{1}{2}\dfrac{\ln
7}{\ln3}\qquad\qquad$d) $x=\dfrac{\ln2}{\ln7}$

La soluci\'{o}n de la ecuaci\'{o}n $5^{8x}=1$ es:\medskip\newline\qquad a)
$x=0\qquad\qquad$b) $x=-\dfrac{1}{8}\dfrac{\ln2}{\ln4}\qquad\qquad$c)
$x=\dfrac{\ln8}{\ln5}\qquad\qquad$d) $x=\dfrac{\ln5}{\ln8}$

La soluci\'{o}n de la ecuaci\'{o}n $5^{2x}=3$ es:\medskip\newline\qquad a)
$x=\dfrac{1}{2}\dfrac{\ln3}{\ln5}\qquad\qquad$b) $x=-\dfrac{1}{2}\dfrac{\ln
5}{\ln3}\qquad\qquad$c) $x=-\dfrac{1}{2}\dfrac{\ln3}{\ln5}\qquad\qquad$d)
$x=\dfrac{1}{2}\dfrac{\ln5}{\ln3}$

La soluci\'{o}n de la ecuaci\'{o}n $4^{2x}=\dfrac{1}{3}$ es:\medskip
\newline\qquad a) $x=-\dfrac{1}{2}\dfrac{\ln3}{\ln4}\qquad\qquad$b)
$x=-\dfrac{1}{2}\dfrac{\ln4}{\ln3}\qquad\qquad$c) $x=-\dfrac{1}{4}\dfrac{\ln
2}{\ln3}\qquad\qquad$d) $x=\dfrac{\ln4}{\ln3}$

La soluci\'{o}n de la ecuaci\'{o}n $9^{2x}=\dfrac{1}{5}\allowbreak$
es:\newline\qquad a) $x=-\dfrac{1}{2}\dfrac{\ln5}{\ln9}$\qquad b)
$x=-\dfrac{1}{9}\dfrac{\ln5}{\ln2}$\qquad c) $x=-\dfrac{1}{5}\dfrac{\ln2}%
{\ln9}$\qquad d) $x=\dfrac{\ln2}{\ln5}$

La soluci\'{o}n de la ecuaci\'{o}n $5^{x}=\dfrac{1}{3}\allowbreak$
es:\newline\qquad a) $x=-\dfrac{\ln3}{\ln5}$\qquad b) $x=\dfrac{\ln3}{\ln5}%
$\qquad c) $x=-\dfrac{\ln5}{\ln3}$\qquad d) $x=\dfrac{\ln5}{\ln3}$

La soluci\'{o}n de la ecuaci\'{o}n $4^{5x}=\dfrac{1}{7}\allowbreak$
es:\newline\qquad a) $x=-\dfrac{1}{5}\dfrac{\ln7}{\ln4}$\qquad b)
$x=-\dfrac{1}{7}\dfrac{\ln5}{\ln4}$\qquad c) $x=\dfrac{1}{7}\dfrac{\ln5}{\ln
4}$\qquad d) $x=-\dfrac{1}{4}\dfrac{\ln5}{\ln7}$

La soluci\'{o}n de la ecuaci\'{o}n $3^{7x}=\dfrac{1}{2}\allowbreak$
es:\newline\qquad a) $x=-\dfrac{1}{7}\dfrac{\ln2}{\ln3}$\qquad b)
$x=-\dfrac{1}{2}\dfrac{\ln7}{\ln3}$\qquad c) $x=-\dfrac{1}{3}\dfrac{\ln2}%
{\ln7}$\qquad d) $x=\dfrac{1}{3}\dfrac{\ln2}{\ln7}$

La soluci\'{o}n de la ecuaci\'{o}n $4^{9x}=\dfrac{1}{4}\allowbreak$
es:\newline\qquad a) $x=-\dfrac{1}{9}$\qquad b) $x=\dfrac{\ln4}{\ln9}$\qquad
c) $x=\dfrac{1}{9}$\qquad d) $x=\dfrac{\ln9}{\ln4}$

La soluci\'{o}n de la ecuaci\'{o}n $3^{2x}=\dfrac{1}{8}\allowbreak$
es:\newline\qquad a) $x=-\dfrac{1}{2}\dfrac{\ln8}{\ln3}$\qquad b)
$x=-\dfrac{1}{2}\dfrac{\ln3}{\ln8}$\qquad c) $x=\dfrac{\ln3}{\ln8}$\qquad d)
$x=\dfrac{1}{3}\dfrac{\ln2}{\ln8}$

La soluci\'{o}n de la ecuaci\'{o}n $7^{5x}=\dfrac{1}{3}\allowbreak$
es:\newline\qquad a) $x=-\dfrac{1}{5}\dfrac{\ln3}{\ln7}$\qquad b)
$x=-\dfrac{1}{7}\dfrac{\ln5}{\ln3}$\qquad c) $x=-\dfrac{1}{3}\dfrac{\ln5}%
{\ln7}$\qquad d) $x=\dfrac{\ln7}{\ln5}$

La soluci\'{o}n de la ecuaci\'{o}n $2^{5x}=\dfrac{1}{9}\allowbreak$
es:\newline\qquad a) $x=-\dfrac{1}{5}\dfrac{\ln9}{\ln2}$\qquad b)
$x=-\dfrac{1}{5}\dfrac{\ln2}{\ln9}$\qquad c) $x=-\dfrac{1}{9}\dfrac{\ln2}%
{\ln5}$\qquad d) $x=\dfrac{1}{9}\dfrac{\ln5}{\ln2}$

La soluci\'{o}n de la ecuaci\'{o}n $10^{2x}=\dfrac{1}{5}\allowbreak$
es:\newline\qquad a) $x=-\dfrac{1}{2}\dfrac{\ln5}{\ln10}$\qquad b)
$x=-\dfrac{1}{2}\dfrac{\ln10}{\ln5}$\qquad c) $x=-\dfrac{1}{5}\dfrac{\ln2}%
{\ln10}$\qquad d) $x=\dfrac{1}{5}\dfrac{\ln10}{\ln2}$

La soluci\'{o}n de la ecuaci\'{o}n $9^{3x}=\dfrac{1}{7}\allowbreak$
es:\newline\qquad a) $x=-\dfrac{1}{3}\dfrac{\ln7}{\ln9}$\qquad b)
$x=-\dfrac{1}{7}\dfrac{\ln9}{\ln3}$\qquad c) $x=\dfrac{\ln9}{\ln7}$\qquad d)
$x=\dfrac{1}{3}\dfrac{\ln9}{\ln7}$


\end{document}